This is a key technical level for Google

Google shares continue to fall after the search engine giant reported weaker-than-expected earnings last week, because of slowing growth in internet advertising and a decline in cost-per-clicks.

The miss prompted a slew of downgrades Friday. Goldman Sachs cut its price target to $600 per share from $625, giving the stock a "neutral" rating. JMP Securities bumped its target down to $640 per share from $695, and Pacific Crest reduced its target from $725 per share to $675.

Google shares are now down 7 percent on the year. So, is it still the value play it once was?

"Over the next three, five, six to twelve years, Google is one of the best positioned companies," said Piper Jaffray's Gene Munster, who believes that despite a disappointing Q3, there is no reason to be concerned about the long-term prospects of Google. "We feel optimistic about the fundamentals."

According to Munster, who has an overweight rating on Google and a price target of $630 per share, investors should take advantage of any pullback as a buying opportunity.

Todd Gordon of Tradinganalysis.com said Google's chart may have broken below a key technical level.

"Google has been an underperformer to the market this year," said Gordon. "Now, [the company] has broken down below its key support level of $540 per share. The next leg down would be to $510, which is that previous low."

Gordon's advice: Wait to see how Google responds to the $510 per share level. "If we break below that level, we have much lower to go. If we hold, the trend is still intact."